Generally described, computing devices and communication networks can be utilized to exchange information. In a common application, a computing device can request content from another computing device via the communication network. For example, a user at a personal computing device can utilize a software browser application to request a page from a server computing device via the Internet or another network. In such embodiments, the user computing device can be referred to as a client computing device and the server computing device can be referred to as a content provider.
From the perspective of a user utilizing a client computing device, a user experience can be defined in part in terms of the performance and latencies associated with obtaining network content over a communication network, such as obtaining a Web page, processing embedded resource identifiers, generating requests to obtain embedded resources, and rendering content on the client computing device. Latencies and performance limitations of a particular client computing device or network may diminish the user experience. Additionally, latencies and inefficiencies may be especially apparent on computing devices with limited resources, such as limited processing power, memory or network connectivity, which may occur on a mobile computing device like a tablet or smartphone. The user experience on certain mobile devices when viewing a given page may also be adversely affected by a limited screen size and/or limited input options (e.g., user interactions being limited to touches on a touchscreen instead of access to a keyboard and multi-button mouse).
For the above and other reasons, website operators or other network content providers will often design different versions of their pages for display on client mobile devices than for display on display monitors of traditional desktop or laptop computers. Pages designed specifically for mobile devices are often referred to as mobile friendly or mobile optimized pages. Relative to a standard version of a given page, a mobile optimized page may include, for example, a rearranged content layout, larger selectable options to account for imprecise touch gestures, and/or other changes. Developers and/or designers often spend substantial time designing mobile optimized pages and testing the usability and appearance of such pages on various mobile devices.